Table 1 Baseline characteristics of participants according to serum 25(OH)D concentrations
Characteristic | Serum 25(OH)D concentrations (nmol/L) | P value | ||||
|---|---|---|---|---|---|---|
Total |  < 25.00 | 25.00–49.99 | 50.00–74.99 |  ≥ 75.00 | ||
Number of participants (%) | 6812 (100) | 244 (3.58) | 1779 (26.12) | 2428 (35.64) | 2361 (34.66) | Â |
Age (years) | 61.00 ± 10.86 | 59.00 ± 10.42 | 60.00 ± 11.05 | 60.00 ± 11.01 | 62.00 ± 10.57 |  < 0.001 |
Race/ethnicity (%) |  < 0.001 | |||||
 Mexican American | 1,064 (15.62) | 42 (17.21) | 381 (21.42) | 449 (18.49) | 192 (8.13) | |
 Non-hispanic white | 3,252 (47.74) | 42 (17.21) | 586 (32.94) | 1,153 (47.49) | 1,471 (62.30) | |
 Non-hispanic black | 1,409 (20.68) | 134 (54.92) | 571 (32.10) | 412 (16.97) | 292 (12.37) | |
 Other hispanic | 595 (8.73) | 17 (6.97) | 144 (8.09) | 243 (10.01) | 191 (8.09) | |
 Other race | 492 (7.22) | 9 (3.69) | 97 (5.45) | 171 (7.04) | 215 (9.11) | |
Education (%) |  < 0.001 | |||||
 Less than 9th grade | 999 (14.67) | 29 (11.89) | 318 (17.88) | 417 (17.17) | 235 (9.95) | |
 9-11th grade | 1,021 (14.99) | 63 (25.82) | 325 (18.27) | 357 (14.70) | 276 (11.69) | |
 High school graduate/GED | 1,738 (25.51) | 60 (24.59) | 453 (25.46) | 591 (24.34) | 634 (26.85) | |
 Some college or AA | 1,823 (26.76) | 64 (26.23) | 455 (25.58) | 643 (26.48) | 661 (28.00) | |
 College graduate or above | 1,223 (17.95) | 28 (11.48) | 226 (12.70) | 418 (17.22) | 551 (23.34) | |
 Not recorded | 8 (0.12) | 0 (0.00) | 2 (0.11) | 2 (0.08) | 4 (0.17) | |
 Family poverty income ratio | 3.04 ± 1.61 | 1.84 ± 1.41 | 2.49 ± 1.64 | 2.86 ± 1.60 | 3.57 ± 1.58 |  < 0.001 |
BMI (%) |  < 0.001 | |||||
 Underweight (< 18.5) | 88 (1.29) | 3 (1.23) | 13 (0.73) | 28 (1.15) | 44 (1.86) | |
 Normal (18.5 to < 25) | 1,701 (24.97) | 38 (15.57) | 301 (16.92) | 568 (23.39) | 794 (33.63) | |
 Overweight (25 to < 30) | 2,151 (31.58) | 58 (23.77) | 500 (28.11) | 845 (34.80) | 748 (31.68) | |
 subjects with obesity (30 or greater) | 2,872 (42.16) | 145 (59.43) | 965 (54.24) | 987 (40.65) | 775 (32.83) | |
Smoking status (%) |  < 0.001 | |||||
 Never smoker | 4,095 (60.11) | 113 (46.31) | 1,027 (57.73) | 1,515 (62.40) | 1,440 (60.99) | |
 Former smoker | 1,722 (25.28) | 60 (24.59) | 415 (23.33) | 586 (24.14) | 661 (28.00) | |
 Current smoker | 991 (14.55) | 71 (29.10) | 336 (18.89) | 326 (13.43) | 258 (10.93) | |
 Not recorded | 4 (0.06) | 0 (0.00) | 1 (0.06) | 1 (0.04) | 2 (0.08) | |
Alcohol intake (%) |  < 0.001 | |||||
 Non-drinker | 2,965 (43.53) | 103 (42.21) | 865 (48.62) | 1,103 (45.43) | 894 (36.87) | |
 1–5 drinks/month | 2,505 (36.77) | 97 (39.75) | 680 (38.22) | 903 (37.19) | 825 (34.94) | |
 5–10 drinks/month | 226 (3.32) | 11 (4.51) | 42 (2.36) | 84 (3.46) | 89 (3.77) | |
 10 + drinks/month | 544 (7.99) | 17 (6.97) | 96 (5.40) | 168 (6.92) | 263 (11.14) | |
 Not recorded | 572 (8.40) | 16 (6.56) | 96 (5.40) | 170 (7.00) | 290 (12.28) | |
Hypertension (%) | 3,670 (53.88) | 150 (61.48) | 986 (55.42) | 1,241 (51.12) | 1,293 (54.76) | 0.051 |
Diabetes (%) | 1,626 (23.87) | 88 (36.07) | 516 (29.01) | 558 (22.98) | 464 (19.65) |  < 0.001 |